The present invention relates to control devices. More particularly, the present invention relates to computer mice having accelerometers to detect motion.
Inertial systems are used in a number of devices such as airplanes, satellites, automobiles, ships, and the like to aid in determining the orientation of these devices in space, orienting these devices in space, and navigation. Inertial systems typically need to be calibrated on a periodic basis to correct for drift accumulated over time. Drift includes the inaccurate reporting of velocity, distance traveled, location, angular velocity, and orientation over time. Drift inaccuracies for velocity occur from errors in the measurement of acceleration and the integration of acceleration to calculate the velocity. As the acceleration is integrated the error is also integrated. The drift is compounded further for distance traveled and location where velocity and the errors in the velocity are integrated. Because a new distance traveled or new location is calculated from a previously calculated distance traveled or location, drift accumulates and increases at a rate roughly proportional to the temporal length of accumulation of acceleration measurements. Therefore, the drift must be periodically corrected so that correct velocity, distance, angular velocity, and orientation may be determined. Drift is often corrected for an airplane or the like by determining actual location and actual velocity by taking a reading from a global positioning system (GPS).
Zilog U.S. Pat. No. 7,688,307 describes “an accelerometer-based mouse.” It describes “A mouse control unit generates a cursor movement disable signal that stops the cursor from moving from the time the mouse is lifted until the mouse is set down. The mouse control unit generates the disable signal by determining the derivative of an acceleration signal for the vertical (z) dimension relative to the working surface.”
Lucent U.S. Pat. No. 5,734,371 describes: “An interactive video/computer pointing system utilizing a magnetic sensor to derive relative azimuthal information, and an inclinometer or accelerometer to provide relative angular elevation information. The azimuthal information is processed to yield an indication of any horizontal movement of the pointing device, and the angular elevation is processed to yield an indication of any vertical movement of the pointing device. This horizontal and vertical movement information is utilized to responsively control a video cursor, thereby enabling the user to point to and select various regions upon a video screen by manipulating the pointing device.”
Tektronix U.S. Pat. No. 4,787,051 describes: “A hand-held inertial mouse provides input data to a computer from which the computer can determine the translational and angular displacement of the mouse. The mouse includes accelerometers for producing output signals of magnitudes proportional to the translational acceleration of the mouse in three non-parallel directions. Pairs of these accelerometers are positioned to detect acceleration along each axis of a Cartesian coordinate system such that an angular acceleration of the mouse about any axis of rotation causes representative differences in the magnitudes of the output signals of one or more of these accelerometer pairs. The translational velocity and displacement of the mouse is determined by integrating the accelerometer output signals and the angular velocity and displacement of the mouse is determined by integrating the difference between the output signals of the accelerometer pairs.”
Sony Ericsson U.S. Pat. No. 7,616,186 describes: “An acceleration reference device comprises an accelerometer that is configured to generate acceleration information that is indicative of movement of the device; a communication interface that is configured to be communicatively coupled to a proximately located computer; a controller that is configured to generate movement information based on the acceleration information from the accelerometer and to communicate the acceleration information through the communication interface to the proximately located computer. The acceleration reference device cooperates with a cellular communication terminal configured to function as a mouse for the proximately located computer or for itself. Related terminal systems and methods are disclosed for using the device to provide mouse type functions.” See also Sony Ericsson U.S. Pat. No. 7,643,850.
Several patents and publications describe detection of movement in 3D and/or detection of movement in air, and using this detected movement to control cursor movement on an associated display. U.S. Pat. No. 5,543,758 describes a remote control that operates by detecting movement of the remote control in space including detecting circular motions and the like. U.S. Pat. No. 6,104,380 describes a control device for controlling the position of a pointer on a display based on motion detected by a movement sensor. U.S. Pat. No. 5,554,980 describes a mouse that detects 3D movement for controlling a cursor on a display. U.S. Pat. No. 5,363,120 claims a system and a method for a computer input device configured to sense angular orientation about a vertical axis. The detected orientation is used to control a cursor position on a screen. U.S. Pat. No. 4,578,674 shows a wireless (ultrasonic) pointer that can also be operated in 3 dimensions. Also, U.S. Pat. No. 4,796,019 shows a wireless handheld pointer to control a cursor by changing angular position using multiple radiation beams. IBM Technical Disclosure Bulletin Vol. 34, No. 11 describes a Gyroscopic Mouse Device that includes a gyroscope that is configured to detect any movement of a mouse to control a cursor on a display. U.S. Pat. No. 5,898,421 describes a gyroscopic mouse method that includes sensing an inertial response associated with mouse movement in 3D-space. U.S. Pat. No. 5,440,326 describes a gyroscopic mouse configured to detect mouse movement in 3D-space, such as pitch and yaw. U.S. Pat. No. 5,825,350 describes a gyroscopic mouse configured to detect mouse movement in 3D-space. U.S. Pat. No. 5,448,261 describes a mouse configured to move in 3D space. U.S. Pat. No. 5,963,145, U.S. Pat. No. 6,147,677, and U.S. Pat. No. 6,721,831 also discuss remote control orientation. U.S. Pat. No. 6,069,594 shows a mouse that moves in 3 dimensions with 3 ultrasonic, triangulating sensors around the display. U.S. Published Application 2005/0078087 is directed to a device which acts as a mouse for a PC when on a surface, detects when it is lifted, then acts as a remote control for appliances. U.S. Published Application 2004/0095317 also discloses a remote control that can be used to control a television and a computer system.
A traditional 3D mouse, such as the traditional mice described briefly above, does not provide the same level of accuracy in determining mouse movement as compared to a mouse having an optical tracking system. Therefore, a 3D mouse used on the same desktop surface as a 2D mouse is typically less accurate in controlling a cursor or the like as compared to a mouse having an optical tracking system. Therefore, new control devices are needed that include inertial systems and provide high accuracy in determining mouse velocity and distance traveled.